/Engine/Source/Runtime/Engine/Classes/Animation/AnimInstance.h
Runs through all nodes, attempting to find all distinct layer linked instances in the group
void GetLinkedAnimLayerInstancesByGroup ( [FName](API\Runtime\Core\UObject\FName) InGroup, [TArray](API\Runtime\Core\Containers\TArray)< [UAnimInstance](API\Runtime\Engine\Animation\UAnimInstance) * > & OutLinkedInstances ) const